work, but thousands are in use. I have always added
> Rich's grid fuse resistor scheme when repairing SB-1000's.
> No tube failures to date that I know of.
You'd be far better off to use a HV glitch resistor, and leave the grid
grounded. Resistors in grid leads are bad news unless there is
good reason to add them, because they let the grid rise to anode
voltage if there is a fault.
If the grid rises to anode voltage, the grid naturally no longer
shields the filament from the HV surge. That means the filament is
many times more likely to rise to B+ rail.
Better to simply put a proper surge resistor in the HV lead, and let
the arc pull the anode low through a series resistance!!!
73, Tom W8JI
W8JI@contesting.com
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